Improvement in machines for threading screw-blanks



No 9677 PATENTBD APR.19,11853.

.- T/NEWBURY.

MACHINE FOR THREADING SCREW BLANKS..

. of a pin' and socket o3.

UNITED *STATES .PATENTv OFFICE.

THOMPSON NEWBURY, OF TAUNTON, MASSACHUSETTS.

'IMPROVEMENT IN MACHINES FOR TI-IRADING'soRIawIsLANKs l.Specification lforming part' of Letters Patent No. 9,677, dated April 19, 1853.

To all whom it may concern:

Be it known that I, THOMPSON Nn URY,

of Taunton, Bristol county, .MassachlsettS,-- have invented certain Improvements lin Mal' chines for .Pointing and ThreadingW ood- Screws, of which the following isv a lfull 'de- Scription, reference being had to the accorti` panying drawings.

Figurel is an taken from Athe'front ofthe machine. Fig. 2 is an end view of the cam-shaft A,exhibitin g the principal cam movements of the machine. I

Fig. 3 is a vertical section of the grip-cone or the cone for operating thel jaw-levers 'or the levers which seize and hold the screw-blanks. The Spindle B, which rotates the screwn blank, carriesthe leader C, which gives the pitch of the thread, the grip-cone' D, which operates the jaw-levers E, andthe j aws e, for holding the screw-blanks. This .spindle receives its motion from the d-rivingfshaft F by means of bevelrgear, as represented, or other Y wise in' any Suitable manner. v

f The cam-shaftA receives its motion from the driving-shaft through endless screw G, gear-wheel H, shaft I, bevel-gear J, and a corresponding bevel-wheel upon Shaft'A, which is hiddenl from view -by wheel J. J

The cam' No. l upon shaft A, Figs. 1 and 2, operates the j aw-levers for seizing and holding the screw-blanks through the` action of the grippone D and the cam-lever A', which has its fulcrum at a.

The cam No. 2 upon shaft A, Figs. l and 2, operatesV the comb-arxn K to press and keep it' upon the leader C and relieve it from the Same at the proper time through the agency of the pusher or sliding rod M and the puller or spring-hook L, which act in opposition to each other upon the spline or rib N upon the tool-post O..

Cam No. 3 upon shaft A operates the tool P, with its carrying-arm Rjthro'u gh the means of cam-1ever S andthe sliding rod T, to which is attached the-former U. The tool-post Q is vin two parts-an upper and a' lower-o o2, which have independent motions on their axes, but move simultaneously up and down. They areconnected by the ordinary device A 4 In the lower part o of .thisdetached tool-post a spiral spring o5 is inserted, this spring being checked above by elevation in perspectiva* thetoolfpost, and the lower end of the spring being checked by the follower V, attached to the short arm of a weighted lever YV.

'y The tool for pointing the screw is con nected with the sliding tool-carrier, which is guidediwithin and supported by the sheath Y. This j sliding tool -carrier is operated ;-tlrrough the cam-lever Z, the fulcrum of which .is ate', by cam 4 on shaft A, Fig. 2. The

cam-lever Z- takes hold of the tool-carrier throughl a vertical slot in the sheath Y, ooncealed from view.

The rest r', against which the screw bears while the threads are out, is attached lto the stand r2. On one side of the rest and attached to the cutting-tool carrier is a guard prevents the screw when delivered from the jaws from getting between the lower end of the spindle and the upperpart of the stand 1012 and injuring the machine.

j The grip-,cone D moves freely up and down on the spindle B, the friction of the ljaw-levers E being sufficient to cause it to revolve with the spindle. Then it is forced down by.

causing themto shut the jaws .e upon the screw-blanks, the lower armsof. these levers being mortised into the jaws, as shown at e e', and the jaws esli'ding in dovetailed grooves in the bottom of the spindle. When the press` grip-cone, the contraction 0f the springs d d closes the upper arms of the j aw-levers E, and the lower arms, opening, release the screw sf after it is finished.

groove (seen at e4 in section, Fig. 3) in which plays a ring or collar' having upon it two proj ections e3 opposite to each other, against which cani-lever A. These projections prevent the ring from turning with the spindle I3. The purpose of this ring is to diminish the friotion between the grip-cone and the ends of the cam-lever A', and being received into the gripcone it prevents the oil from beingv thrown out by centrifugal action. The upper portion of the gripcone is provided with a l circular groove e5, (seen in Fig. 1 and in sec a 'shoulder within the cavity of this part of r3, consisting of a bentv piece of metal which the cam-lever A', it spreads the vupper arms j of the jaw-levers, closes their lower. arms,

ure of the cam-lever A is relieved from the On the upper face of the grip-cone D is av rest the extremities of the arms of the forked periphery oith'e cam 1. l into' operation when the end of the slide-rod 2 l n u 9,677'

The machinery-beingin motion,by.th e revo?4 lution of.v the cam'1 in t he direction of the arrowpmthel end of leverAis brought vupon .the periphery of thecamland the jaws are x closed tight upon tlie'sciew-blank; Thenth'e "c'aml begins to depress-the lever Z, -thereby y raisinginthe ,tool-'carrier X forrpointing the screw, which being' done by tool fr 'while' it is d rising, the projection or cam 4 soon passes by 'the armof lever Z and theitool-carrier. X is forced down outof the wayby the spiral spring. m2, attached toits lower end. y During the time of feeding, gripping, and pointing the screwblank'thecams Zand 3 'are' inoperative in consequence ofthe pusher or sliding rod. M land the cam-lever S passing, respectively,'over --the long depressions on thesurface of these cams; Meanwhile the lever A is still on the The cam 2comes M rides upon vprojection e A of this cam. This causestheslide-rod to press upon. the spline N on the upper part of the tool-post, which carries the comb-arm K and brings the combarm into contact with the leader'G, The cam 3 begins to operate at [about the saineV time or immediately after can 2.v When the caml'ever S rides upon Athe projection b" of this pam, it vforces thelsliding rod T against the to'ol-carryingarm R, bringing thetool P up againstthe screw-blank.. The upper part of the tool-posto' now begins tod'escend .by the action of'the leader C upon the conib-arni QK,4 carrying with it the lower part of .the tool-post o2, 'and with it the lower part the threading-tool .Pf In the iirst part of the descent of the tool-post that end of the. arm R which rests against the former U passes over aportion of the surface of lthe former, which is. perpendicular to the same plane with the spindle B, thereby causing the tool P through this por-r tien lof its. descent to cut the blank` to an equal depth. .Jlhe'lowerp'ortion of` the facel ofthe former `is raised in order to throw theA tool? in toward the center-of the screw-blank cut the thread upon the point ofthe same.A When the first cut of the thread is finished, the threading-tool I. must be moved away from the screw-blank, and immediately thereafter the comb-arm K must be removed from the leader,'in order to allow the tool-post to Pise and bring the comb-arm and the threadng-tool f into ay position to commenceanothercut.- A.This is accomplished by means ,of i c springs S2 S3, whichoperate, respectively, to force the pusher M and lever Sinto tho depressions upon their lappropriatecams.'

When both the threading-tool and ,comb-arm are disengaged, the tool-post rises by the ac.- tion' of the. Weighted lever W until its top strikesthe e adjusting-screw S4. 'Ihe combarm is then brought upon the leader and th'e threading-tool brought up to the blank by the l means already specified for the first cut, and the second is performed in thesame manner as the 'iirst cut; but in order to make the second cut 'thethreading-tool must-approach a little neare'r'to the center of the'screw-blank,

land this is accomplished bymaking the projections on cam 3 each successively' a little rising or fartherfrom the center of the 'c am. Thel operations ofA removingl the threadingtool and thecomb-arm, the rising of the toolpost, and the next cut of the thread are again repeatedl andas many times as maybe deemed necessary lto make a perfect thread. In the vlp'resent arrangement provision is made for nine outs# When these cuts are completed,

4the tool and the comb-anulare' moved out of the way, as before, with the exception that the toolis removed farther from the screw, in consequenceof the cam-lever S falling into the deep depression on.. cam 3, in order that the screw with its head may not strike the tool as it drops from the jaws. The tool-post having risen, the threading-tool and comb-arm stand away from the screw and leader, respectively, until another screw-blank is fed in, gripped, and pointed. This'is in consequence of. the

pusher M and cam-lever S falling into theV long depressions -on their appropriate cams 2 3. At this vtime the friction-roller n2 on tue endof cam-lever` A falls into the deep depression on cam l, allowing the grip-cone D- to rise on the spindle B by the action of the springs d/which-close the jaw-levers E E upon the inclined surface of the grip-cone, thereby` opening the jaws e e and releasing the screw, which falls into a suitable receptacle, The'operation is here completed, and' -then repeated, as already described.

In regard to the detached tool-post, there are important advantages connected with the arrangement and4 construction adopted. It beingnecessary that thecomb-armand threading-toolfshould have independent motions,

and at the same time certain connected movements, the construction of the post in two portions detached and at the same time connecte'd, as4 described, enables me to make or cast the comb-arm whole with its portion of the post and .the tool-carrying arm whole with its portion of the post and to dispense with extramachinery and save room in the machine. y.

The mode of preventing the rebound of the tool-post is peculiar and important. If the tool-post were carried Aup by a weight `or by a spring the postwould rebound; but by interposing the'springin the peculiar manner between the post and the weightedlever the rebound is prevented. The spring within the tool-post is always under tension, tending to press the post upward and the follower down- Ward, and .any tendency of the post to rebound in consequence of the vibration of the Weighted lever or otherwise is counteracted Vby the tension of the spring operating upon the follower V, connected. with the weight- Vlever.

The operation of the pusher direct from th cam upon the splineon the upper part of the..

tool-post is an improvement` in'this special connection and saves the introduction of an intermediate Ashaft and gearing used inv other,

screw-machines for this purpose.

I ,have 'described the guard -rs'as attached.v

to the threading-tool arm; but thesaniepur pose may be answered by having the guard Y or its equivalent attached to the rest r.

In other machines for making screws itis usual to make the rest movable, so as to Wit-hdraw it'when the screw isliberated from the jaws in consequence of the liability of the Screw to get between the rest and the spindle vandbreak orfderange the machine; but by means of the guard I can use a fixed rest, and by means of both l can use ahigh speedwithout danger, the guard operating to check the whirling motion ot' the screw, which it Vfrequently gets on leaving the jaws. JPhe advantage of a iixed rest over a movable o ne is too obvious to need explanation.

The friction-ing recessed into therrrpper face of the grip-cone is an improvement upon the ordinary method of a ring lying flat upon the saine, or offriction-rollers, as' from its extended bearingsurface and its depression below the upper` face of the grip-cone it prevents the escape of the oil orlubricating material employed in this part and Wears for a longer time and is not liable to get out vof order. I

The employment of the separate pointingtool operated in the manner described pre- .sents a 'decided advantage over the usual mode'of pointing with the threading-tool or "one connected therewith. It saves the threading-tool for its proper function, allows of greater simplicity, and consequently steadiness of its notio'ns, and gives greater capacity to the machinefandby adopting a motion for the pointing-tool in a line parallel with the spindle, as set forth, lavoid complication and 

